Flexible stay-bolt.



I. G. HUNTER.

FLEXIBLE STAY BOLT. APPLIOATIOH rum) JULY 9, 1907..

Patented Nov. 14, 1911.

FREDERICK GEORGE HUNTER,.OF MONGTON, NEW BRUNSWICK, CANADA.

FLEXIBLE STAY-BOLT.

Specification of Letters Patent.

Patented Nov. 14, 1911.

Application filed July 9, 1907. Serial No. 382,968.

To all whom it may concern:

Be it known that I, FREDERICK GEORGE HUNTER, a citizen of the Dominionof Can, ada, residing at the city of Moncton, in the county ofl/Vestmoreland and Province of New Brunswick, Canada, have inventedcertain new and useful Improvements in Flexible Stay-Bolts, of which thefollowing is a specification.

The invention relates to improvements in flexible stay-bolts for use inconnecting the plates or sheets of steam boilers, and other purposes,and it consists in the novel features hereinafter described, andparticularly pointed out in the claim.

The object of the invention is to provide an improved stay-boltstructure adapted to securely hold the plates or sheets in properrelation to each other and to yield at one or both ends with theexpansion and contraction of said plates.

The stay-bolt of my invention is preferably, though not in all instancesnecessarily, composed of three members, one of these being a stud orbolt threaded at both ends and the other two being externally andinternally threaded sockets to engage threaded holes in the boilerplates and receive the ends ofsaid stud or bolt, a distinguishingfeature of the structure being that the stud or bolt while engaging thesaid sockets has atone or bothends'a loose threaded-connection therewithand therein, whereby said bolt is prevented from drawing out from thesockets but may have a limited oscillating motion therein and thus yieldto the expansion and contraction of the plates. Preferably the threadedends of the stud or bolt will be slightly tapered, and said ends may befastened within their sockets by transverse pinsv whose ends willclosely engage the sockets and whose middle portions will loosely engagethe bolt.

The invention will be fully understood from the detailed descriptionhereinafter presented, reference being had to the accompanying drawings,in which:

Figure 1 is a horizontal section portion of the outer and inner sheetsor plates of a steam boiler with the flexible stay-bolt of my inventionin position connecting the same; Fig. 2 is a vertical section through aportion of the plates or sheets connected by a modified form ofstay-bolt embracing some of the features of, my invention; Fig. 3 is avertical section of same through on the dotted line 8-3 of Fig. 2; Fig.4 is a section corresponding with Fig. 2, illustrating a furthermodification of my invention, and Fig. 5 is a section through one end ofa further modification of the bolt and its socket, the constructionpresented in Fig. 5 diifering from that shown in Fig. 1 in the characterof the threads formed on the end of the bolt and within the socket.

In the drawings, referring to Fig. 1, 10 designates the fire-box plate,11 the outer shell-plate, 12 the stud or bolt proper, 13 the innersocket member and 14 the outer socket member, said sockets tightlyengaging threaded holes in said plates and being connected by said studor bolt. The stud or bolt 12 is threaded at its ends. The innersocket-member 13 has an internally threaded socket 15 and an externallythreaded shank 16, whose outer end after having been passed through thehole in the plate 10 is headed, as at 17 The inner threaded walls of thesocket 15 are straight and engage the threaded end of the bolt 12 with aloose thread-connection, the inner diameter of said socket being greaterthan the end of the bolt, whereby oscillation of the bolt is permitted.The end of the bolt is further secured within the socket 15 by means ofa pin 18 which tightly fits holes in the side walls of said socket andpasses through a free aperture 19in said bolt, said pin thus alsopermitting the bolt to have an oscillatory action when necessary. Theouter socket member 14 contains an internally threaded socket 20 and has.an outer poly onal head 21. adapted to receive a wrench or applyingtool. The inner walls of the socket 20 are straight and engage theirthreaded end of the bolt 12 with a loose thread-connection, the innerdiameter of said socket being greater than the end of the bolt, wherebyoscillation of the bolt is permitted. The end of the bolt is furthersecured within the socket 20 by means of a pin 22 which tightly fitsholes in the side walls of said socket and passes througha free aperture23 in said bolt, said pin thus also permitting the bolt to have anynecessary oscillatory action. The clearance in the stud orbolt-apertures 19, 23 is also desirable in that during the heading orriveting of the outer end of the shank 16, they permit the ends of thebolt to abut against the solid ends of the sockets and take the strainsdue to such heading or riveting.

In the construction shown in Fig. 1, the parts of the bolt-structure areassembled prior to their application to the sheets 10, 11,

and the socket-member 13 is introduced through the hole 24 in the sheet11 and then screwed, at its shank 16, through the hole 25 in the sheet10, the socket-member 14 during this action being screwed into said hole24, after which the outer end of the shank 16 is headed or riveted.During the application of the stay-bolt structure, the pins 19, 22,compel the socket-members and stud 12 to rotate together.

The stay-bolt structure shown in Fig. 1 will very securely andefliciently connect the sheets 10 and 11 and allow said sheets to expandor contract without creating any detrimental effects, the loosethread-connection at the ends of the stud 12 permitting the latter tofreely oscillate during such expansion or contraction. It is notnecessary in every instance to provide for the oscillatory action atboth ends of the stud 12 but it is desirable in some cases, and hence inpresenting the preferred form of my invention I arrange for theoscillation at both ends of said stud.

In the construction shown in Fig. 2, 30 designates the stud or bolt, 31the inner socket member, and 33 the outer socket member, said member 33differing from the socket member 14 shown in Fig. 1 only in thecharacter of the threads out within the same. The stud or bolt 30corresponds with the stud or bolt 12 of Fig. 1 except in that it has adifferent style of thread out upon it, the threads on the ends of thebolt or stud 30 being on the same plane but forming a loosethread-connection with the threads of the socket members 31, 33, so asto permitof the oscillatory action of the bolt during the expansion andcontraction of the sheets 10, 11. The socket member 31 is in the form ofa hollow plug closed at its outer end and externally threaded to engagethe threaded hole in the sheet 10. The bolt or stud 30 is connected withthe socket members 31, 33 by pins 34 corresponding with the pins 18, 22,of Fig. 1. The stay-bolt structure shown in Fig. 2 is applied toposition in the manner above described with respect to the structureshown in Fig. 1, with the exception that the socket member 31 is screwedinto its receiving hole in the sheet 10 and is not headed. The loosethreadconnection of the stud or bolt 30 with the socket members 31, 33admits of an oscillatory action of the bolt at either end, and it is oneof the purposes of my invention that the stud or bolt 30 at one or bothends shall have a. loose thread-connection so as to insure the properoscillatory action of the bolt during the expansion and contraction ofthe sheets 10, 11.

In the construction shown in Fig. 4, 40

designates the stud or bolt, 41 the inner socket member, and 42 theouter socket member, said stud or bolt and outer socket membercorresponding exactly with the stud or bolt and outer socket member ofFig. 2, with the exception that they employ a difierent style of screwthread. The inner socket member 41 corresponds with the inner socketmember of Fig. 2, with the exception that it employs a difierent styleof screw thread and is formed at its outer end with a head 43 to receivea wrench or other applying tool, the inner socket member 41 not beingfastened to the stud or bolt 40 by means of a pin, but intended forseparate application to the sheet 10 and to receive the inner end of thestud or bolt 40, which is connected with the outer socket member 42 by apin 44. I present Fig. 4 to indicate that the invent-ion is not limitedto the special style of screwthreads shown in Fig. 2, nor, in everyinstance, to the connection of the inner socket member with the innerend of the bolt or stud by a pin. The ends of the stud or bolt 40 have aloose thread-connection with the socket members 41, 42, and hence-whilebeing prevented from withdrawing from said members, may have anoscillatory action at one or both ends during the expansion andcontraction of the sheets 10, 11.

In Fig. 5 I illustrate a portion of a modified form of stay-boltstructure, the modification consisting in utilizing a different style ofthread on the end of the bolt or stud 45 and within the socket member 46shown in Fig. 1, the end of the stud or bolt being threaded and taperedand having a loose thread-connection with the socket member, wherebysaid bolt may have an oscillatory action during the expansion andcontraction of the boiler plates.

In all of the forms of the invention illustrated the ends of the stud orbolt have a loose thread-connection with the socket members, and mayconsequently have an oscillatory action therein, and in addition thestaybolts shown in Figs. 1 and 2 may, in their entirety, be introducedthrough the outer shell or plate of the'boiler. I prefer that the endsof the stud or bolt be tapered so as to increase the extent to whichsaid ends may oscillate within their sockets, but find that efficientresults may be attained when the ends of the bolt and the inner walls oftheir sockets are parallel with and loosely engage each other, the endsof the bolt being less in diameter than the threaded sockets whichreceive them.

I do not limit the invention to the particular character of threadswhich may be out upon the ends of the stud or bolt and the inner wallsof the socket-members, nor in every instance is the invention limited tothe assembling of the stud or bolt and socketmembers prior to theapplication of the structure to position, but I deem it advantageous toassemble the parts, as shown in Figs. 1 and 2, and introduce the samethrough the outer shell or plate 11.

All of the socket-members will preferably be slightly tapered on theirexterior so as to firmly wedge into their receiving holes in the sheets10, 11. The socket 31 is tapered outwardly because it is screwed intothe plate 10 from the inner side thereof, and the socket 41 is taperedinwardly because it is screwed into the plate 10 from the outer sidethereof.

The loose thread-connection of the ends of the stud or bolt with thesocket-members not only permits the oscillation of the bolt but thefrequent movement of the threads on the bolt toward and from theinternal threads on the sockets serves to cut away any sediment whichmight otherwise gather in the sockets and interfere with the flexibilityof the stay-bolt structure.

What I claim as my invention and desire to secure by Letters Patent, is:

A flexible stay-bolt structure for connecting two parallel plates andengaging threaded alined holes in said plates, said structure comprisinga stud threaded at both ends,

means securing one end of said stud to one of said plates, meanssecuring the other end of said stud to the other plate comprising anintegral internally and externallythreaded socket member adapted to thethreaded hole in said other plate and having a solid outer end and beingopen at its inner end to receive one end of said stud, and a transversepin extending through said socket member and the end of said stud andfreely connecting said parts together so that without prejudice to theflexibility of the structure said socket member while carrying said studmay be passed to its seat in its plate and the free end of the studscrewed into its securing means at the other plate, said socket memberhaving an interior bore of greater diameter than and engaging with itsthreads its end of said stud, whereby said socket member and said studhave a loose thread connection permitting oscillation of the stud;substantially as set forth.

Signed at Moncton, New Brunswick, Canada, this fifth day of July, 1907.

FREDERICK GEORGE HUNTER. Witnesses:

AUSTIN A. ALLEN, E. Ross HUNTER.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, D. 0.

